* PDP-11 , Announcement 1970, DEC's first and only 16 bit computer *
Detailed information about the origin and history of the PDP-11 family are available on many sides in the Internet, such as at WIKIPEDIA or at PDP11.ORG.

Several PDP-11 systems were saved from the scrapping and are scattered worldwide in museums or in private collections. The PDP-11 systems are splitted in two categories, the Q-BUS based systems and the UNIBUS based systems. Different CPU-Chips/microprocessor were developed during the life's cycle of the PDP 11 systems. The Q-BUS based area started with the legendary PDP-11/03 system in 1976. This system never became „sell“ but “distributes“. The demand was extremely high.
My saved systems are a PDP-11/23 SE ( Special Edition ) based on Q BUS with specifically developed components and a DEC professional 350. In the following chapter both systems are described exactly.